Further to my last post, the FAA in America have grounded all the Boeing 787s currently flying after two battery-related incidents this year (1). This includes an in-flight fire (2) that took fire crew forty minutes to extinguish whilst the plane was on the ground.
The 787 is revolutionary in several ways - most prominently the extensive use of carbon-fibre, but also for it's 'all-electric' architecture. Amongst other things, this means that pressurisation is not performed by bleed-air off the engines, but by using compressors.
A desire to reduce weight led to lithium-ion batteries being used, which allow the batteries to be smaller and lighter than those used in other planes. This technology is relatively new in aerospace, and lithium-ion batteries carried as freight are suspected to have caused at least one crash already and numerous other problems. (3)
The administration building of the firm who created the charging system for the 787's batteries burnt to the ground in 2006 after a battery caught fire. Additionally, a 787's Power-Control Panel caught fire during flight testing in November 2010 (4), causing further large delays in its entry into service. Whilst such problems are to be expected in flight test, it does look worrying with hindsight, and asks serious questions about Boeing's knowledge of the 787's electrical systems.
So what does this mean for Boeing? it is unlikely that the flight ban will be lifted until the reason for the battery fires are understood and fixes developed. These fixes (they can be fairly simple or massively complex - we should not prejudge) then need applying to each airframe. This will certainly take time and be costly.
Initial suspicions are that the batteries are overcharging. If this is the case (and it may take some time to know for certain and to reproduce), then there are issues of why such problems were not experienced or anticipated before. Boeing will not want to replace the lithium-ion batteries with alternative batteries that are heavier and bulkier.
Worse, the FAA certified the use of Lithium-Ion batteries on the 787, a first for civil aircraft. If the certification process has been proved wrong, their burden of proof for safety will be much higher this time around. As well as alterations to prevent the batteries from catching fire, they may well insist on systems to negate the effects of any fire.
In the meantime, the uncertainty means it will be hard for prospective purchasers to arrange funding for 787s. And this gives an advantage on Airbus, who were massively behind with their competing A350, but who are catching up due to Boeing's woes. Although they have plenty of time to develop their own problems with the A350...
(1): http://www.flightglobal.com/news/articles/analysis-grounding-orders-moves-787-into-uncharted-territory-381148/
(2): http://blogs.crikey.com.au/planetalking/2013/01/15/burned-787-battery-underlines-seriousness-of-incident/
(3): http://gigaom.com/2011/04/04/lithium-ion-batteries-faulted-for-jet-crash/
(4): http://www.flightglobal.com/blogs/flightblogger/2010/11/a-closer-look-787-fire-investi.html
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